Stitching machines

ABSTRACT

A machine for performing an operation on a work piece passing therethrough is disclosed with such machine including a work surface for supporting the work piece as it passes through the machine; pull roll means for advancing the work piece in a first direction of travel through the machine; and work application means, for example a stitching head, for performing a stitching operation on the work piece, said work application means being selectively movable in a second direction transverse to the first direction of travel of the workpiece. The pull roll means comprises at least one pull roller provided on a pull roll shaft for rotation therewith and slidable motion therealong in the aforementioned second direction of travel of the work application means. The pull roller includes at least first and second unidirectional clutches carried on the shaft with the first unidirectional clutch being capable of rotation on the shaft in one direction and incapable of rotation on the shaft in an opposite direction, and the second unidirectional clutch being capable of rotation on the shaft in the opposite direction and incapable of rotation on the shaft in the one direction. In this manner, the pull roller must rotate with the shaft but may slide therealong.

iJnited States Patent 1 Harland [451 July 24, 1973 STITCHING MACHINES [75] Inventor: Lauri C. Barland, West Chester, Pa.

[73] Assignee: Precision Industries, Inc., Baltimore,

[22] Filed: Aug. 18, 1971 [21] Appl. No.: 172,834

Primary Examiner-Granville Y. Custer, Jr. Attorney-Lawrence l. Lerner et al.

571 ABSTRACT A machine for performing an operation on a work piece passing therethrough is disclosed with such machine including a work surface for supporting the work piece as it passes through the machine; pull roll means for advancing the work piece in a first direction of travel through the machine; and work application means, for example a stitching head, for performing a stitching operation on the work piece, said work application means being selectively movable in a second di rection transverse to the first direction of travel of the workpiece. The pull roll means comprises at least one pull roller provided on a pull roll shaft for rotation therewith and slidable motion therealong in the aforementioned second direction of travel of the work application means. The pull roller includes at least first and second unidirectional clutches carried on the shaft with the first unidirectional clutch being capable of rotation on the shaft in one direction and incapable of rotation on the shaft in an opposite direction, and the second unidirectional clutch being capable of rotation on the shaft in the opposite direction and incapable of rotation on the shaft in the one direction. In this manner, the pull roller must rotate with the shaft but may slide therealong.

3 Claims, 5 Drawing Figures PArcmcumw 3.747.823

SHEU 1 BF 2 INVENTOR. LAURI C. BARLAND LERNER,DAVID 8 LITTENBERG ATTORNEYS PATENTED M24195 3. 747. 82 3 SNEEI 2 0F 2 STITCHING MACHINES BACKGROUND OF THE INVENTION In the formation of cardboard (corrugated) cartons by stitching machinery, the appropriately folded box blank is passed through the stitching machine beneath a work station at which a stitching head consecutively applies wire stitches to the overlapped portions of the box blank. Means are customarily provided to rotate pull rollers mounted on a pull roll shaft to advance the box blank in an appropriate fashion through the machine and beneath the stitching head. In a continuous feed machine, the pull rollers are continuously rotated during each feed of a box blank, whereas in an incremental feed machine, the pull rollers are incrementally rotated in a stop and start fashion, syncronized with the stitching head, to cause the box blank to experience an instantaneous dwell at the moment that a stitch is applied by the stitching head.

Because of the variations in width of the box blanks to be stitched, it is essential that the pull rollers for advancing the blank be capable of lateral sliding motion along the pull roll shaft. Thus the pull rollers must be fixed on the pull roll shaft for rotation therewith but yet slidable therealong.

In the prior art, the aforedescribed characteristics of the pull rollers on the pull roll shaft are customarily provided by a conventional keyway arrangement in which a key provided within the pull rollercentral passageway is slidably received in a groove or keyway provided along the length of the pull roll shaft. As well knownin the art, such arrangement keys the pull roller for rotation with the pull roll shaft but at the same time permits the pull roller to be slid along the shaft.

Despite the lateral motion of the pull rollersprovided by the above described arrangement, it has been found that existing stitching machinery is still not wide enough to accept the extremely large box blanks which will produce the larger cartons sometimes required by the ultimate user. Attempts to accomodate such extra wide box blanks by simply widening the entrance throat of the stitching machine have proved unsatisfactory primarily because, depending upon the shape of the box to be ultimately manufactured, the overlapping portions of the blank to be stitched do not uniformly appear at the same location on the work table. Hence, for each different type of box blank, the machine must be set up (for example by laterally moving the side rails which guide the blank in its forward movement through the machine) to make sure that the overlapping portions of the box blank are properly aligned with the stitching head.

SUMMARY OF THE INVENTION In an effort to provide a universal stitching machine which does not require a new set up each time the box blank seam appears at different location, the inventor hereof has turned to a traveling stitching head. That is, the stitching head of the machine of the instant invention is carried by a support member selectively movable in a direction laterally transverse with respect to the direction of travel of the box blank through the machine. Thus, regardless of the location of the overlapping portions of the box blank, and by means of actuating mechanism to be described in detail, the operator can simply move the stitching head in the required lateral direction and effect the desired seam.

Moreover, when the traveling" stitching head of the instant invention is employed in a wide jumbo machine designed to accomodate extremely wide box blanks (and in which the traveling stitching head concept is most advantageously employed), a serious problem has been encountered in connection with the aforedescribed keyway arrangement for the pull rollers thereby necessitating a completely new pull roller arrangement constituting an invention in of itself.

Specifically when the aforedescribed groove of the prior art keyway arrangement is provided along the entire length of an extremely long pull roll shaft, the shaft tends to weaken and bow especially after extended periods of use. Such bowing is completely unacceptable.

In accordance with this aspect of the instant invention, the novel pull rolls include a hub having a central passageway in which first and second unidirectional clutches are secured with the pull roll shaft passing through the unidirectional clutches. One of the unidirectional clutches is rotatable in a first direction on the pull roll shaft but not rotatable in the opposite direction. The second unidirectional clutch is rotatable in the opposite direction but not rotatable in the first direction. Thus the back to back unidirectional clutches guarantee that the pull roller will rotate with the pull shaft but at the same time will be capable of being slid therealong.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING FIG. 1 is a perspective view of a portion of a stitching machine constructed in accordance with the instant invention.

FIG. 2 is a front view partly in section, showing the novel pull roll construction of the instant invention.

FIG. 3 is a view of the pull roller of FIG. 2 taken along the lines3-3 thereof. v

FIG. 4 is a view of the pull roller of FIG. 2 taken along the lines 4-4 thereof. 7

FIG. 5 is a sectional view of a pull roller constructed in accordance with an alternative embodiment of the instant invention.

DETAILED DESCRIPTION Turning to the drawings, there is illustrated in FIG. 1 a stitching machine designated 10. Broadly spraking, the machine 10 includes a work surface or table 12 upon which a box blank 14 is supported as it is passed through the machine 10. To advance the box blank 14 there is provided a pair of pull rollers 16 and 18 carried by a pull roll shaft 20 journaled for rotation in upstanding portions of the machine frame 22 and driven by a pulley and belt arrangement broadly designated 24 which links the shaft 20 to a drive shaft 26 appropriately driven by mechanism (such as an electric motor not shown and forming no part of the instant invention).

Positioned above the work surface 12 in a manner to I be further described is a stitching head 28 which in a manner well known in the art, applies consecutive wire stitches to the overlapping portions 30 and 32 of the box blank 14 as the box blank is advanced, through the machine in response to rotation of the pull rollers 16 and 18. Since the stitching head per se forms no part of the instant invention, a detailed description is not provided herein, it being understood that any conventional stitching head may be employed in the practice of the instant invention. Alternatively, the stitching head 28 may be of the type described and claimed in U.S. Pat. application Ser. no. 37,190 filed May 14, 1970, now U.S. Pat. 3,642,187, issued Feb. 15, 1972, in the name of Lauri C. Barland entitled Stitching Head and assigned to the assignee of the instant invention. Regardless of the type of stitching head employed, a conventional guide shoe (not shown) is secured to the stitching head therebeneath for guiding the portions 30 and 32 of the box blank 14 as the blank passes beneath the head 28.

As thus far described, the stitching machine is similar to prior art stitching machinery and the differences therebetween will now be presented. However before going into detail, it should be noted that although the following inventions are specifically described in the environment of a wire stitching machine for applying wire stitches to a corrugated box, the principles hereof are applicable to any machine in which a work piece is advanced by pull rollers past a work station where some work application means is to perform an operation thereon.

Returning to the particular environment of the wire stitching machine 10, it is seen that positioned above the work surface 12, carried by the frame 22, is a guide rail 34 which carries a support member or trolley 36 which rides or travels along the guide rail 34 by means of rollers 38 carried thereby. Carried on the front surface of support member 36 is an angle bracket 40 on the front wall 42 of which is fixedly secured a vertically orientated guide channel 44 having a channelway 46 therein. On the rear of the stitching head 28 is provided a similarly shaped elongated projection 48 which dovetails in the channelway 46 to permit the stitching head 28 to be vertically adjusted with respect to the angle bracket 40 and hence the support member 36. A locking screw 50 passes through the wall 42 and the rear portion 52 ofthe guide channel 44 and into the channel way 46 thereof and into locking frictional engagement with the projection 48. When it is desired to raise or lower the stitching head 28 with respect to the work surface 12, the operator simply unscrews the locking screw 50, raises or lowers the stitching head 28 to the desired vertical position, and then retightens the locking screw 50.

As noted previously, the support member 36 (and hence the stitching head is intended to travel in the direction of the double-headed arrow 54 along the guide rail 34 in order to properly position the stitching head 28 with respect to the overlapping portions 30 and 32 of the box blank 14. In this manner, for a given box blank width (indicated by the dimension W), the side rails 56, 58 provided on the surface 12 do not have to be changed regardless of the location of the overlapping portion of the box blank. For example, if for the particular box being constructed, the overlapping portions of the blank are located at the positions in phantom at 30' and 32', rather than move the box blank to the left as viewed in FIG. 1 (thereby necessitating the movement of the rails 56 and 58), with the instant invention, the operator simply moves the stitching head 28 along the guide rail 34 toward the right as viewed in FIG. 1 until the stitching head 28 is positioned above the overlapping portions 30' and 32'.

To affect such desired lateral movement, the support member 36 includes an upstanding internally threaded projection 60 through which is passed an externally threaded lead screw 62. The lead screw 62 is coupled by a coupling member 64 to the output shaft 66 of an electric motor 68. Thus operation of the motor in a clockwise or counterclockwise direction will cause similar rotation of the lead screw 62 thereby causing the projection 60 (with the support member 36 and stitching head 28 carried thereby) to travel laterally left or right as viewed in FIG. 1.

It will thus be appreciated that the invention thus far described in a most simple, efficient manner permits the stitching head to be moved laterally with respect to the work surface 12. Furthermore, the angle bracket 40 assures that the stitches produced by the 28 will be angularly oriented in a manner suggested at 70 in FIG. 1 (such angular orientation being preferred in the box stitching industry).

As was further noted previously, when the traveling stitching head concept described above was applied in a jumbo" (extra wide) stitching machine, an intolerable situation occurred with respect to the manner which the pull rollers 16 and 18 were mounted on the pull shaft 20. Thus with extremely long pull roll shaft 20, the keyway grooved therealong caused the shaft to weaken and bow. This problem has been completely eliminated by the provision of a unique pull roller arrangement described hereinbelow, which completely eliminates the key and keyway arrangement of the prior art.

Turning to FIG. 2, there is shown an enlarged, par tially sectioned, view of the pull rollers 16 and 18 carried by the pull roll shaft 20. Since the pull rollers 16 and 18 are identical, only the pull roller 16 will be de scribed in detail.

Pull roller 16 includes a hub 72 having a central passageway 74 therethrough and a gripping surface 76 (of rubber or other suitable material) disposed thereabout. Secured within the passageway 74 in back to back relationship are first and second unidirectional clutches 78 and 80 having central passageways 81 and 82 (FIGS. 3 and 4) through which passes the pull roll shaft 20.

The unidirectional clutches 78 and 80 are identical and may be of the type manufactured for example by the Torrington Company, Torrington, Conn. Without going into great detail, and with reference to FIG. 3, when the shaft 20 is rotated in a counterclockwise direction, internal springs 84 bias the roller 86 into camming engagement with the angled surface 88 thereby causing the entire clutch housing 78 (and pull roller 16) to rotate in a counterclockwise direction indicated by the arrow 90. With respect to the clutch 78 of FIG. 3, should the shaft 20 to be rotated in a clockwise direction, the rollers 86 will be urged in a clockwise direction against the bias of the internal springs 84 to an enlarged vicinity not in camming engagement with the angled surface 88. Hence clockwise rotation of the pull roller 16 is prevented.

As noted, the clutch 80 of FIG. 4 is identical to clutch 78. However in accordance with the invention, the clutch 80 is secured within the hub 72 of the pull roller 16 in a reverse orientation on the pull roller shaft 20. That is the clutch 80 is oriented to permit rotation of the pull rollerl6 in a clockwise direction but not permit rotation of the pull roller in a counterclockwise direction. The net result of providing the back to back clutches 78 and 80 in a reversed mode is that one clutch prevents rotation of the pull roller 16 on the shaft 20 in a first direction, while the second clutch prevents rotation of the pull roller 16 on the shaft 20 in the opposite direction. Hence, by the back to back reversed unidirectional clutch arrangement of the instant invention, the pull roller 16 must rotate directly with the pull roll shaft 20. At the same time, pull rollers 16 and 18 can be easily slid along the pull roll shaft 20 in accordance with the width of the box blank being fed thereby.

Turning to FIG. 5, there is shown an alternative embodiment of the instant invention in which three unidirectional clutches 92, 94, and 96 are secured in back to back relationship in the hub 16'. Clutches 92 and 96 are oriented in the manner that clutch 78 was oriented and clutch 94 is oriented in the manner that the clutch 80 was oriented. Thus, the pull roller 16' cannot rotate relative to the pull roll shaft 20'. In addition, the third clutch 96 positioned on the opposite side of the clutch 94 has been found particularly useful for balancing the torques involved especially at extremely high speeds of operation.

Although this invention has been described with respect to its preferred embodiments, it should be understood that manyvariations and modifications will now be obvious to those skilled in the art, and it is preferred, therefore, that the scope of the invention be limited, not by the specific disclosure herein, only by the appended claims.

I claim as my invention:

1. A machine for performing an operation on a work piece passing therethrough, said machine comprising:

a work surface for supporting said work piece as it passes through said machine;

pull roll means for advancing said work piece in a first direction of travel; and

work application means for performing said operation on said work piece, said work application means being selectively movable in a second direction transverse to said first direction of travel; and wherein said work application means is supported on a support member selectively movable in said second direction; and further including means for selectively moving said support member in said second direction; and further including a guide rail positioned above said work surface; said support member being supportingly guided for movement in said second direction by said guide rail; wherein said work application means is vertically adjustable with respect to said support member; wherein said work application means is angularly carried on said support member;

wherein said pull roll means comprises at least one pull roller provided on a pull roll shaft for rotation therewith and slideable motion therealong in said second direction of travel; and

wherein said pull roller includes at least first and second uni-directional clutches carried on said shaft, said first uni-directional 'clutch being capable of rotation on said shaft in one direction and incapable of rotation on said shaft in an opposite direction, said second uni-directional clutch being capable of rotation on said shaft in said opposite direction and incapable of rotation on said shaft in said one direction. 1

2. A machine for performing an operation on a work piece passing therethrough, said machine comprising:

a work surface for supporting said work piece as it passes through said machine;

pull roll means for advancing said work piece in a first direction of travel; and work application means for performing said operation on said work piece, said work application means being selectively movable in a second direction transverse to said first direction of travel; and

wherein said work application means is supported on a support member selectively movable in said second direction;'and further including means for selectively moving said support member in said second direction; and

further including a guide rail positioned above said work surface; said support member being supportingly guided for movement in said second direction by said guide rail;

wherein said work application means is vertically adjustable with respect to said support member; wherein said work application means is angularly carried on said support member; and

' wherein said means for selectively moving said support member comprises an internally threaded projection carried by said support member and an externally threaded lead screw passing in screw threaded engagement through said projection; rotation of said lead screw moving said support member in said second direction.

3. The machine of claim 2, wherein said support member is of generally U-shaped configuration including a top bight portion and a pair of depending side portions; said internally threaded projection carried on said bight portion said work application means being angularly carried by and vertically adjustable with respect to one of said depending side portions. 

1. A machine for performing an operation on a work piece passing therethrough, said machine comprising: a work surface for supporting said work piece as it passes through said machine; pull roll means for advancing said work piece in a first direction of travel; and work application means for performing said operation on said work piece, said work application means being selectively movable in a second direction transverse to said first direction of travel; and wherein said work application means is supported on a support member selectively movable in said second direction; and further including means for selectively moving said support member in said second direction; and further including a guide rail positioned above said work surface; said support member being supportingly guided for movement in said second direction by said guide rail; wherein said work application means is vertically adjustable with respect to said support member; wherein said work application means is angularly carried on said support member; wherein said pull roll means comprises at least one pull roller provided on a pull roll shaft for rotation therewith and slideable motion therealong in said second direction of travel; and wherein said pull roller includes at least first and second unidirectional clutches carried on said shaft, said first unidirectional clutch being capable of rotation on said shaft in one direction and incapable of rotation on said shaft in an opposite direction, said second uni-directional clutch being capable of rotation on said shaft in said opposite direction and incapable of rotation on said shaft in said one direction.
 2. A machine for performing an operation on a work piece passing therethrough, said machine comprising: a work surface for supporting said work piece as it passes through said machine; pull roll means for advancing said work piece in a first direction of travel; and work application means for performing said operation on said work piece, said work application means being selectively movable in a second direction transverse to said first direction of travel; and wherein said work application means is supported on a support member selectively movable in said second direction; and further including means for selectively moving said support member in said second direction; and further including a guide rail positioned above said work surface; said support member being supportingly guided for movement in said second direction by said guide rail; wherein said work application means is vertically adjustable with respect to said support member; wherein said work application means is angularly carried on said support member; and wherein said means for selectively moving said support member comprises an internally threaded projection carried by said support member and an externally threaded lead screw passing in screw threaded engagement through said projection; rotation of said lead screw moving said support member in said second direction.
 3. The machine of claim 2, wherein said support member is of generally U-shaped configuration including a top bight portion and a pair of depending side portions; said internally threaded projection carried on said bight portion said work application means being angularly carried by and vertically adjustable with respect to one of said depending side portions. 